Apparently the upgrade decided to reset almost every one of my settings including RBLS but the most frustrating setting it reset was the disk threshold check. I monitor my own disks and don't care to get the overzealous 5-20 e-mails a minute telling my that a file system unrelated to zimbra is over 80%.

I remember from 5.0.18 that a key/value within zmlocalconfig could define the threshold so I set that :
$ zmlocalconfig | grep threshold
zimbra_disk_threshold = 100
zmdisklog_critical_threshold = 99
zmdisklog_warn_threshold = 98

But I still seem to be getting these e-mails (although less frequently):
zimbramon[xxx]: xxx:err: Disk warning: server.domain.com: /dev/mapper/vg00-www at 88%

I've restarted ZCS in hopes of getting rid of them altogether. In 5.0.18, there was a file I modified.. something in /opt/zimbra/libexec but I couldn't find that file in 6.0.2.

Also.. I tried to turn off AV notification in the administration area but I get this message when I try and 'save' the settings: